Shantungosaurus wins. It's too massive and powerful for the Spinosaurus, or for any theropod for that matter. I would give the Shantungosaurus a winning chance of around ~90%.

To everyone saying that the freaking theropod would have the advantage, please explain without using bad analogies like that human vs dog thing as arguments, while using logic, not that extremely biased "it's a herbivore vs predator, predator auto win" nonsense.

And for the fight I'd personally go with shantungosaurus, as it was at least 3 tons larger in terms of mass, and in 9/10 of predator vs prey encounters the predator is either overwhelmed or made to retreat.

Not sure why. Herbivores where in fact just as impressive as carnivores, as they were able to colonise and grow to titanic promotions (the sauropods), and developed thick and advanced body armour making them far more durable (the ceratopsians). I personally prefer spinosaurus, but shantungosaurus deserves just as much respect and would defeat all theropods (not simultaneously) in a one on one confrontation the majority of the time.

Well, physically a human would easily defeat a dog, as we are much larger, heavier, and we are quite robust. However, since we are easily freaked out, we would just simply succumb to the dogs attacks in pure fear.

Before many days i saw picture of Zhuchengosaurus as big as Shantungosaurus or slightly bigger than that and today i read that it was a synonym.Anyway,i wanted one hadrosaur and of course you know i am all about big...LOL.

When i saw a picture of Shantungosaurus before many days,i wondered what the hell is that.I didn't knew a Hadrosaur was that big.Before that as i knew they were the size of an Elephant.I was impressed by its size and thought,damn...i want Shantungosaurus.